Single Comment

The application of en passant in Alice Chess is really not that confusing.
The opposing Pawn must have immediately performed a two-step move to the
capturing Pawn's field, resulting in a position orthogonal adjacent. The
cell which the capturing Pawn is moving to must be vacant, in both fields.
This denotes that the single step was a viable option for opposing Pawn.
If that cell on the capturing Pawn's field is occupied by either friend
or foe, en passant is not viable since the single step of the opposing
Pawn was not possible and thus capture of that Pawn on that cell was not
an option. If it is occupied by an another enemy, a simple capture of
this enemy piece is still possible but this would not result in the
capture of the opposing two-stepping Pawn.